WASHINGTON, D.C. - An independent panel says the National Security Agency's collection of Internet data within the United States passes constitutional muster and employs "reasonable" safeguards designed to protect the rights of Americans.

The Privacy and Civil Liberties Oversight Board has largely endorsed a set of NSA surveillance programs that have provoked worldwide controversy since they were revealed last year by former NSA contractor Edward Snowden. However, the board said some aspects of the programs merit new safeguards.

In January, the board said a different NSA program - its collection of domestic calling records - "lacked a viable legal foundation" and should be shut down.